Goldstone CA DSS-14
We basically use another dish in the area to transmit radio waves at some celestial body. It could be a planet like Mars (we helped scout the landing spot for the two latest rovers!), or an asteroid, etc. We then use this dish to catch the

DSS-14, Goldstone California
This is NOT my photo - Photo courtesy of NASA/JPL-Caltech.

I administer a network of Sun and Linux computers in the base of this dish. We are moving more and more to Linux because it's many times cheaper, many times faster, and much easier to maintain. However, I still use an old, cranky Sun Sparc10 as an NIS server here (believe it or not). My Linux machines do the important work however - curse you Solaris!!! We recently used my machines here to image near earth asteroid

DSS-14, Goldstone CA (Mars)
www.flickr.com/photos/sgt_spanky/35811144/in/set-874253/
Radar pr0n.
We use a small bank of Linux machines in the base of this dish to help image celestial bodies using deep space radar. The dish looks small from this perspective, but it's actually 70-meters (230-feet) in diameter - capable of tracking a spacecraft traveling more than 16 billion kilometers (10 billion miles) from Earth.
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